iOS绘制虚线方法

/**
** lineView:      需要绘制成虚线的view
** lineLength:    虚线的宽度 //2
** lineSpacing:        虚线的间距//1
** lineColor:    虚线的颜色
**/
+ (void)drawDashLine:(UIView *)lineView lineLength:(int)lineLength lineSpacing:(int)lineSpacing lineColor:(UIColor *)lineColor
{
CAShapeLayer *shapeLayer = [CAShapeLayer layer];
[shapeLayer setBounds:lineView.bounds];
[shapeLayer setPosition:CGPointMake(CGRectGetWidth(lineView.frame) / 2, CGRectGetHeight(lineView.frame))];
[shapeLayer setFillColor:[UIColor clearColor].CGColor];
//  设置虚线颜色为blackColor
[shapeLayer setStrokeColor:lineColor.CGColor];
//  设置虚线宽度
[shapeLayer setLineWidth:CGRectGetHeight(lineView.frame)];
[shapeLayer setLineJoin:kCALineJoinRound];
//  设置线宽，线间距
[shapeLayer setLineDashPattern:[NSArray arrayWithObjects:[NSNumber numberWithInt:lineLength], [NSNumber numberWithInt:lineSpacing], nil]];
//  设置路径
CGMutablePathRef path = CGPathCreateMutable();
CGPathMoveToPoint(path, NULL, 0, 0);
CGPathAddLineToPoint(path, NULL, CGRectGetWidth(lineView.frame), 0);
[shapeLayer setPath:path];
CGPathRelease(path);
//  把绘制好的虚线添加上来
[lineView.layer addSublayer:shapeLayer];
}